Blue cotton dye and process of making same.



TYNITED STATES PATENT OFFICE.

AUGUST LEOPOLD LASKA, OF OFFENBAOH-ON-THE-MAIN, GERMANY, ASS IGNOR TOOHEMISCHE FABRIK GRIESHEIM-ELEKTRON, OF FRhNKFORT-ON-THE MAIN,

GERMANY, A CORPORATION.

Specification of Letters Patent.

Patented July 16, 1907.

Application filed March 22,1907. Serial No. 363,938-

To all whom it may concern:

Be it known that I, Auons'r LEOPOLD LASKA, doctor of philosophy,chemist, and a resident of 5 Gerber- .strasse, Offenbach-on-the Main, inthe Grand Duchy of Hesse, Germany, have invented new and usefulImprovements in Blue Cotton Dyes and Process of Making Same, of whichthe following is a specification.

My invention relates to the manufacture of new cotton dyes produced bycombining tetrazotized diamidobases with one molecular proportion of aperi-dioxynaphthalene sulfoacid and one molecular proportion of 2arylamido 5 naphthol 7 sulfoacid. The thus obtained dyestuffs dye cottonviolet to blue shades of excellent brightness surpassing in this pointsimilar commercial azodyes. The 2 arylamido 5 naphthol 7 sulfoacid, em-

. ployed in the manufacture ofthcse dyestuffs, makes them fast to sodiumcarbonate so that they can be dyed in an. alkaline or neutral bath.

Among .thediamidobases benzidin, tolidin or diani- V sidin may be used.

I The following example will serve to illustrate my invention; partsbeing by weight: A solution of the tetrazo-compound, obtained from 12.2parts of dianisidin in the well known manner, is poured into an ice coldsolution of 18.2 parts of 1:8 dioxy naphthalene 3:6 disulfoacid (sodiumsalt) containing a SllfilClCllt quantity of sodium acetate to remove theexcess of hydrochloric acid. When the intermediate product is 'matterprecipitated by addition of common salt. dyestuff, in a dry state beinga black powder, dissolves formed the solution is rendered alkaline bysodium carbonate and a neutral solution of 16 parts of 2 phenylj'amido 5.naphthol7 sulfoacid is added. To complete the formation of the dyestuffthe mixture is stirred for twelve hours, heated up to 70 C. and thecoloring The in concentrated sulfuric acid to a greenish blue, in waterto a reddish blue solution. The color of this solution is hardly alteredby addition of caustic soda lye In the production of this coloringmatter the 1:8 dioxy-naphthalene 3:6 disulfoacid can be replaced by anyother peridioxy-naphthal ene sulfoacid, for instance by the 1:8dioxy-naphthalene 3:5 disulfoacid; the 2 phenylamido 5 naphthol 7sulfoacid can be replaced by any other arylcompound f. i. by thetolylamidonaphthol sulfoacid. All the thus obtained dyestuffs dyecottonvery bright blue tints. In employing other diamidobases f. i.benzidin or tolidin dyestuffs are obtained, which dyemorc reddishershades on cotton.

Now what I claim and desire to secure by Letters Patent is thefollowing:

1. The process of ma'nufacturlng new cotton dyestuffs, which consists incombining the tetrazocompounds of the said dialnidobases with. onemolecular proportion of a 55 peridioxynaphthniene sulfoncid and onemolecular proportion of a 2 arylamido 5 naphthol 7 sulfoacid.

2. The process of manufacturing new cotton dyestn flzs which consists incombining the tetrazocompound of dianisidin with one molecularproportion of a peridioxynaphthalene sulfoaeid and one molecularproportion of 2 arylamido 5 nuphthol 7 sulfoacid.

3. As a new article of manufacture the dyestuffs obtained by combiningthe tetrazocompounds of dian'lsidln with one molecular proportion of aperidioxynaphthalene 65 sulfoacid and one molecular proportion of 2arylamido 5 naphthol 7 sulloneid, being brown black powders, dissolvingin concentrated sulfuric acid to a greenish blue, in water to a reddishblue solution, and dyeing cotton very bright blu tints.

4. As a new article of manufacture the dyestuifs obtained by combiningthe tetrnzocompound of dianlsidin with one molecular proportion of 1 :8dioxynaphthalene 3 :6 dlsulfoncid and one molecular proportion of 2urylumldo 5 nuphthol 7 sulfoncid, being brown black powders, dis 75solving in concentrated sulfuric acid to a greenish blue, in water to areddish blue solution, and dyeing cotton very bright blue tints.

in testimony, that I claim the foregoing as my invention, I have signedmy name in presence of two witnesses, 80 this seventh day of March 1907.

AUGUST LEOIOLD LASKA.

Witnesses EVA SATTLER, HEHMANN Winn.

